See the image below for more information. I would like to recreate the pixellated effect on the left side of the image. This will be a batch process so I thought I can just select all the inner space and use inner glow/shadow to output some gradient. I vaguely remembered I did this in high school haha but I forgot how. How can make an inner gradient glow like the left image? Note I used red color just to make everything more clear, the end product should use black lines and produce same pixelated and corrupted effect like the left side.

Things I have tried: I tried to select the outside of the red line and the inside but inner glow/shadow are applies to the lines?

Does layer style only works on shape layers? If then how can I convert my entire line art into a shape layer? I suppose I could just do a quick googling. Thanks. Sorry I forgot to mention I will not be creating these lineart shapes, I would like to just select the inner space of an already created image and apply the glow effect. Which mean I have to convert the line art image into a shape layer to use this correct?
– Inkplay_Jul 7 '18 at 17:55

@Inkplay_ No, layer styles work on any kind of layer, but really an inner glow effect is only going to work on a layer that has artwork which is somewhat solid. It's not going to be visible on something that is just lines without a fill. I suppose you could select inside the lines you have already, create a new layer, fill the selection with white, and then apply an inner glow to it.
– Billy KerrJul 7 '18 at 18:14